TM 5-5420-227-24
TONGUE CYLINDER RELIEF VALVE (RV4) ADJUSTMENT (Sheet 1 of 1)
TOOLS: 3/16 in. socket head screw key
1/4 in. socket head screw key
9/16 in. openend wrench
SPECIAL TOOLS: Adapter ell (item 1, sec III, app B)
Adapter straight (item 2, sec III, app B)
Gage, pressure (item 3, sec III, app B)
Hose assembly (item 4, sec III, app B)
Two
PERSONNEL:
REFERENCE:
Remove tongue cylinder armor (page 3-226)
PRELIMINARY PROCEDURES:
Relieve hydraulic pressure (page 3-65)
NOTE
If STE/ICE is available, go to STE/ICE
Test 51 (page 2-47).
ADJ USTMENT:
Using 1/4 inch screw key, remove plug (A).
1.
2.
Manually install gage assembly in opening left by plug (A) removal.
Engage hydraulic pump (TM 5-5420-226-10).
3.
4.
Set engine speed at 1800 rpm.
Slowly push down tongue cylinder control lever all the way until tongue cylinder
5.
(B) is in fully retracted position.
Have second technician observe pressure gage reading.
6.
7.
Return tongue cylinder control lever to neutral position.
8.
Using wrench, remove adjusting screw cap (C).
NOTE
Correct pressure is 3600 50 psi (24622 340 kPa).
To adjust relief valve pressure, hold adjusting screw (D) with 3/16 inch screw key
9.
and use wrench to loosen jamnut (E). Using 3/16 inch screw key, turn adjusting screw
(D) clockwise to increase pressure or counterclockwise to decrease pressure.
10.
Repeat steps 3 through 9 until pressure gage shows reading of 3600 + 50 psi (24822 +
--
--
340 kPa).
11.
Holding adjusting screw (D) with 3/1 6 inch screw key, use wrench to tighten jamnut
(E).
Remove gage assembly.
12.
13.
Using 1/4 inch screw key, install plug (A).
Install adjusting screw cap (C) using wrench.
14.
15.
Install tongue cylinder armor (page 3-227).
TA170304
End of Task
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